Opzioni selvicolturali su cedui di leccio del Gargano: risultati a 14 anni dall'avvio della sperimentazione

In the frame of a long-term research program concerning management of ageing holm oak coppices, results available after 14 growing seasons are reported in present paper. Experimental treatments include: A) 50 standards per hectare, all of the same age; B) 250 standards per hectare, all of the same age; C) 140 standards per hectare, with two different ages; D) conversion to high forest; E) natural evolution (control). A total of 15 permanent plots were established (5 treatments x 3 replicates per treatment) and the experimental design used is that of randomised blocks. Based on observations concerning seedlings and shoots development and standards growth and competitive effects, the following preliminary results may be highlighted: i) recovering the traditional coppicing system with few standards per hectare represents a valid option from both ecological and shoots growth point of view; the stools, with few standards per hectare, showed a larger number of sprouts, provided with a higher average height and larger diameters; ii) uneven-aged standards represent a good alternative form the points of view of both landscape impact immediately after felling operations and stand resistance to climatic damages; iii) a good alternative is to apply conversion treatments to high forest, whenever their site quality allows these operations.